Packaging system for protection of ic wafers during fabrication, transport and storage

ABSTRACT

The packaging system includes an enclosure having an interior volume. A wafer stack, comprising plural wafers and separators in contact with the wafers, is located in the interior volume. The separators have raised bumps extending from each side. The bumps create spaces that allow air to flow therethrough. The separator film intercepts and captures airborne molecular contaminants belonging to organic and inorganic chemical families. In addition, the film is dissipative to static discharge. Furthermore, the bumps provided by the separators protect the fragile wafers from damage due to mechanical shock. The separators are also provided with a peripheral ring or embossment, which contacts the wafer edges and further protects the wafers from damage to mechanical shock. Air cushions can be provided in the wafer stack, which cushions are provided with bands to regulate the compression.

This application claims the benefit of U.S. provisional application Ser.No. 61/434,194, filed Jan. 19, 2011.

FIELD OF THE INVENTION

The present invention relates to a packaging system for protectingintegrated circuit (IC) wafers.

BACKGROUND OF THE INVENTION

Since the beginning of IC wafer fabrication, manufacturers have wagedwar against corrosive contaminants, relying on processing equipmentwithin, clean rooms having filters, monitors and/or mini-environmentsusing containers identified as PODs, FOSBs (front opening shipping box)and/or FOUPs (front opening unified pod). These containers employ theconcepts of Standard Mechanical Interface (SMIF). The clean rooms andcontainers have the purpose of significantly reducing IC die yieldlosses traceable to airborne molecular contaminants (AMCs). Examples ofAMCs are HF (hafnium), HCL (hydrochloride) and VOC (volatile organiccompounds). Although AMCs remain elusive, they are traceable to indoorand outdoor chemical activities.

Nitrogen purging (pressure method) is one prior art method of thereducing AMCs in the wafer container and use of a vacuum is the other.However, both are expensive and tend to move the AMCs to other locationswhere they can cause problems.

Even, further, these same manufacturers are known to employwafer-packaging methodologies that specify containers with little or noadequate features to simultaneously control breakage, corrosive and/orelectrical damage to packaged IC wafers during transport and/or storagephases after fabrication phases for further downstream processing. Thisoversight can add to the reduced IC die yields after probing phases andbefore bonding phases.

AMCs known to cause corrosive damage to IC wafers being fabricatedwithin clean rooms mostly belong to the organic and inorganic chemicalfamilies. Inorganic AMCs such as HL, H2S, HNO3 and HCL are mostlytraceable to indoor chemical activities required for wafer fabricationand organic AMCs such as CnHx are mostly traceable to outdoor activitiessuch as vehicle exhaust fumes. Further, wafer boxes, separators andcushions requiring “chemical additives” to achieve dissipative (10E5 to<10E11 ohms) surfaces to avoid electro-static discharge (ESD) events canoutgas AMCs resulting in corrosive damage to surfaces of packagedwafers. Even further, there is the additional problem defined as “wavesof mechanical shock energy” traceable to container mishandling that cancreate breakage damage to packaged wafers during transport and/orstorage phases. Accordingly present day wafer shipping containers havelithe or no features to simultaneously address breakage, corrosive andESD damages all of which could result in reduction in IC die yields.This can be a serious problem for 21st Century IC wafers such as 300 mmand 450 mm sizes with smaller geometries having much faster speeds. Thisrelates to said problem traceable to the fact at one point in timecorrosive AMCs within environments of containers packaged with wafersduring fabrication, storage and/or transport stages were consideredharmless, but now are attributed to costly IC die losses traceable tochemical interaction with AMCs.

SUMMARY OF THE INVENTION

The present invention provides a packaging system for the protection ofIC wafers during fabrication, transport and storage phases. The wafershave surface components such as bond pads, solder balls andinterconnects which are susceptible to damage due to corrosion,mechanical shock and/or electrical static discharge. The packagingsystem comprises an enclosure having an interior volume in which a waferstack is located. The wafer stack comprises plural wafers and separatorsin contact with the wafers. Each separator has two sides and has raisedhumps extending from each side of the separator sheet. The bumps createspaces between the respective separator and the respective wafer, whichspaces allow air to flow there through. At least one of the separatorsis made of a polymer film material having the properties to interceptand capture airborne molecular contaminants hereinafter referred to asAMCs belonging to either or both chemical organic and inorganic familiesfor which the material is dissipative to static discharge.

In accordance with one aspect of this invention, the separator is aplastic :film material comprises activated carbon and a component takenfrom, the group of copper, aluminum, tin, silver and a rare earth.

In accordance with another aspect, the wafers have edges subject tomechanical shock. The separators are sheets, the separators havingperipheral rings located adjacent to the wafer edges so as to protecteach associated packaged wafer edge from shock or physical damage.

In accordance with another aspect, the peripheral rings are embossed inthe separator sheets.

In accordance with another aspect, a support ring made of a polymer, islocated adjacent to the separator, the support ring is rigid.

In accordance with another aspect, at least one cushion is located inthe wafer stack to absorb mechanical shock energy. The cushion comprisesa compressible core and a flexible envelope around the core. Theenvelope has vents to allow gas to pass in and out of the top and bottomcushions at a controlled rate. The top and bottom cushions havesidewalls that compress when the top and bottom cushions are compressed.A flexible hand is located around the side wall of at least one of thetop and bottom cushions. The band is located outside of the cushionenvelope and controls the flow of gas into and out of the respectivecushion.

In accordance with another aspect, the enclosure is a rigid plastic boxhaving electrically insulative surfaces.

In accordance with another aspect, the wafer stack is dissipative tostatic discharge.

In accordance with another aspect, the box can be stacked onto similarboxes. The box has top and bottom conductors on the outside and providean electrical, path to earth ground for the wafer stack. The top orbottom conductors are in contact with the top or bottom conductors of anadjacent box stacked with the one box.

In accordance with another aspect, the enclosure is a bag.

In accordance with another aspect, the enclosure is a rigid box within abag.

In accordance with another aspect, a packaging system intercepts andcaptures corrosive contaminants for the protection of IC wafers duringfabrication, transport and storage phases. The wafers have surfacecomponents such as bond pads, solder balls and interconnects which aresusceptible to damage due to corrosion, mechanical shock or electricalstatic discharge. The packaging system comprises an enclosure having aninterior volume and surrounding walls. A wafer stack is located in theinterior volume. The wafer stack comprises plural wafers, with spacethere between to allow air to flow therethrough. A sacrificial materialis located in the interior volume and has activated carbon and a metal.The sacrificial material intercepts and captures airborne molecularcontaminants (AMCs), tie material being dissipative to static discharge,the sacrificial material located adjacent to at least one of the walls.

In accordance with another aspect, the sacrificial material is a filmand the metal is taken from the group of copper, aluminum, tin, silverand a rare earth.

In accordance with another aspect, the sacrificial material is a filmthat is coupled to a metal, stud in at least one of the walls.

In accordance with another aspect, the sacrificial material is a film,further comprising a support that is coupled to the sacrificialmaterial.

In accordance with another aspect, the sacrificial material is a pouch,the pouch having perforated walls made up of sacrificial material film,the pouch having a pouch interior, the pouch interior containingsegments of the film.

In accordance with another aspect, the packaging system furthercomprises separators between the walls and the wafer stack. Theseparators have raised bumps extending therefrom. At least one of theseparators is made of the sacrificial material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective exploded view of a container and bag.

FIG. 2 is a perspective view of the container of FIG. 1 located in thebag.

FIG. 3 is a cross-sectional view taken through lines III-III of FIG. 2.

FIG. 4 is a detailed cross-sectional view of a portion of the waferstack of FIG. 3, in accordance with one embodiment.

FIG. 5 is a perspective exploded view of a wafer and a separator of FIG.4.

FIG. 6 is a detailed cross-sectional view of a portion of the waferstack, in accordance with another embodiment.

FIG. 7 is an exploded perspective view of a wafer, separator and ring ofFIG. 6.

FIG. 8 is a plan top view of an air cushion.

FIG. 9 is a cross-sectional view of the cushion of FIG. 8, taken throughlines IX-IX.

FIG. 10 is a perspective view of the cushion.

FIG. 11 is a cross-sectional view of a wafer stack in accordance withanother embodiment.

FIG. 12 is a perspective partially exploded view of a POD shown with afilm having sacrificial surfaces.

FIG. 13 is an exploded view of the POD of FIG. 12.

FIG. 14 is a cross-sectional view of an ESD arrangement, taken throughlines XIV-XIV of FIG. 12.

FIG. 15 is a perspective view of an open FOUP shown with the film havingsacrificial surfaces.

FIG. 16 shows a pouch made of film having sacrificial surfaces.

FIG. 17 is a cross-sectional view of FIG. 16 taken through linesXVII-XVII.

FIG. 18 is a cross-sectional view of an ESD arrangement of FIG. 15.

DESCRIPTION OF THE PREFERRED EMBODIMENT

There is described a packaging system and method for protecting ICwafers during fabrication, transport and storage. The packaging systemand method decrease IC wafer die losses by: 1) reducing contaminantsthat come into contact with the IC wafers, which contaminants causecorrosion damage; 2) absorbing mechanical shock energy, thereby reducingwafer breakage; and 3) providing electrical conductivity to dissipateelectrostatic discharge.

Contaminants that damage IC wafers are airborne molecular contaminants(AMCs) and can be of the organic type and inorganic type. These AMCsmove around and contaminate IC wafers using environmental moisturevapors. In an analogy, the moisture vapors are “taxi-cabs” thattransport the AMCs throughout an environment. The system as describedallows for the circulation of these moisture vapors throughout thepackaging system and provides sacrificial surfaces intercept and capturethese AMCs before the AMCs reach the IC wafers.

The prior art uses either nitrogen purging or vacuuming the interior gasin a wafer container in order to remove contaminants. These prior arttechniques remove moisture vapors from the container. This is incontrast to the system described herein, which does not seek to removethe moisture vapors from a vapor container. Instead, the sacrificialsurfaces are used to intercept and capture, or isolate, the moisturevapors.

We have discovered that AMCs travel on moisture vapors. As an analogy,the moisture vapors are “taxi-cabs” that move the AMCs around. Thesystem isolates and captures the moisture vapors and the AMCs associatedtherewith.

IC wafers are fragile and prone to breakage if dropped or bumped. Thesystem as described provides protection of the IC wafers so that if thecontainer or enclosure housing the IC wafers is dropped or otherwisesubjected to mechanical shock energy, the shock energy is absorbedwithout damaging the IC wafers.

Electrostatic discharge, if improperly handled, can result in electricaldamage to the IC wafer circuitry. The system as described protects theIC wafers against electrostatic discharge (ESD) events by providing apath to electrical ground at a certain resistance. Specifically, theresistance is 10E5 to 10E11 ohms.

The system as described utilizes enclosures or containers. Suchenclosures include PODs, FOUPs and FOSBs, all of which are conventionaland commercially available. Another enclosure 20 is shown in the figuresherein (see FIGS. 1 and 3). Still another enclosure is a bag 30 having aflexible wall.

The IC wafers 25 are conventional and can be of any size, for example150-450 mm. During the fabrication process, the IC wafers are initiallyconsidered to be “before probing”. Certain enclosures may be used tohouse the IC wafers before they are probed. In probing, electrical testsare made to the electronic circuits on the IC wafers. After probing,certain other specialized containers may be used to house the IC wafers.The present invention can be utilized with enclosures used to containthe wafers before and with containers that contain the wafers afterprobing, as the IC wafers are subject to damage from AMCs, mechanicalshock and ESD throughout the fabrication process, as well as duringtransport from one fabrication location to another, as well as duringstorage while the IC wafers await the next fabrication or transportstep.

In the description, like reference numbers indicate like components.

FIGS. 1 and 2 illustrate container 20 and bag 30 whereas said containeris packaged within said bag. The packaged unit 10 is shown in FIG. 2.The enclosure is the packaged unit 10. The enclosure can also be thecontainer 20 by itself or the bag 30 by itself. The container need notbe used with the bag. Likewise, the bag need not be used with thecontainer. Container 20 is made from a plastic resin having no carbon.Carbon by nature, as a material, has moisture vapor absorbing cells andis used within most present day wafer shipment containers to avoid ESDevents. However this is a recipe for a warehouse to absorb environmentalmoisture vapors laced with environmental corrosive AMCs thus producing“corrsive soups” that could damage surfaces of packaged wafers. On theother hand, bag 30 is made of special polymer film that reacts with andpermanently neutralizes all reactive AMCs (inorganic) and absorbs allother AMCs (organic) within container 20. Specifically container 20 isdesigned for not absorbing moisture vapors that could be laden withenvironmental AMCs.

FIG. 3 is a cross-sectional view of the packaged unit 10. The container20 has a top cover 21 and a bottom cover 22. The enclosure contains awafer stack made up of wafers 25, wafer separators 27 and activated aircushions 23. There is an air cushion 23 located in bottom cover 22 andanother air cushion 23 is located in top cover 21. A separator 27 isprovided between each two adjacent wafers 25. The container 20 isenclosed and placed inside of the bag 30, through an end 31 that neednot be sealed and remains open. The open end 31 of said bag 30 has thepurpose to accept the presence of environmental moisture vapors in theinterior space 13. Some amount of environmental moisture vapors lacedwith some amount of AMCs will always reside within the enclosureinterior space 13 and said vapors will always be mobile and thereforewill become “taxi-cabs” to transport said residing AMCs to thesacrificial surfaces of separators 27 and surface of said hag 30 forwhich both have the ability to chemically react with and permanentlyneutralize said AMCs belonging to the inorganic family and absorb allother AMCs belonging to the organic family. The sacrificial surfaces“intercept and capture” moisture vapors and AMCs to protect the packagedIC wafers from “corrosive damages” during shipment and/or storagestages.

The bottom cover 22 is provided with multiple rubber type verticalisolators 22 b peripherally located therein for which arrangementassociates with an air cushion 23 located in bottom cover 22corresponding with or relating to an air cushion 23 located in top cover21. The combination of multiple vertical isolators 22 b in unison withcushions 23 as an assembly within container 20 has the purpose toprohibit or restrict vertical and/or lateral motion that can damagepackaged wafers traceable to improper packaging methodology whilesimultaneously absorbing mechanical shock energy traceable tomishandling of container 20 during any transport phase. The packaged ICwafers are protected from “motion related damages” during shipmentand/or storage stages.

FIG. 4 is a detail cross-sectional view of the portions of the waferstack 26, while FIG. 5 shows a wafer 25 and a separator 27. The wafer(s)25 are separated by one or more separators 27. In the preferredembodiment, there is a separator 27 between adjacent wafers 25. Eachseparator 27 is a sheet-like material having two sides (referring to theorientation of FIG. 4, a top side and a bottom side). Bumps, orembossments, 27 a, 27 b extend out from each side. Thus, bumps 27 aextend upwardly from the top side and bumps 27 extend downwardly fromthe bottom side. The bumps 27 a are spaced apart from each other;likewise, the bumps 27 b are spaced apart from each other. The bumps maybe arranged in rows, with every other bump 27 a extending in onedirection and the remaining bumps 27 b extending in the oppositedirection so as to evenly distribute the bumps. When the wafers arestacked as shown in FIG. 4, with a separator 27 between each two wafers25, the bumps 27 a, 27 b form standoffs that contact the circuit sideand back side of the adjacent wafers. Air can circulate through thespaces 28 a, 28 b between the wafers and the separators, which spacesare created by the bumps 27 a and 27 b.

The separators 27 are made from a polymer sacrificial film, or capturematerial, having one or more layers. The film is a polymer, activatedcarbon and a chemically reactive metal such as copper, aluminum, tin,silver or a rare earth, such as samarium. For specifics on the film,reference is made to U.S. Pat. Nos. 4,944,916 and 5,154,886, the entiredisclosures of which are incorporated herein by reference. In oneembodiment, the film has three layers, namely a first copper layer, acarbon layer and a second copper layer, with the carbon layer beinginterposed between the two copper layers. As an alternative, the filmcan have two layers, one of copper, the other of carbon. Each layer hasa polymer. Examples of suitable polymers are polyethylene andpolypropylene. The copper layers have polymer and copper (or otherreactive metal) while the carbon layer has the polymer and activatedcarbon. The layers are bonded together. The separator film interceptsand isolates AMCs, whether of the organic or inorganic type. As the airmoves through the spaces, or reactive zones, 28 a, 28 b, the inorganicAMCs are neutralized by the separator film and the organic AMCs areabsorbed by the separator film. In particular, it is believed that thecopper, or other metal in the separator film, neutralizes the inorganic.AMCs while the organic AMCs are absorbed by carbon in the film. The AMCsdo not contact the IC wafers and do not cause corrosive damage.

The bumps 27 a, 27 b not only create spaces 28 a, 28 b, but also serveto reduce mechanical shock energy transferred to the wafers 25, such asif the enclosure 10 is dropped. The bumps have some “give” orflexibility that serve to cushion the wafers in the event of amechanical shock

The bumps 27 a, 27 b cushion the wafer stack along a longitudinal axisof the wafer stack, wherein the wafers are oriented transversely to thelongitudinal axis. Thus, in FIG. 4, the longitudinal axis would bevertical. The separators 27 also cushion the wafers 25 from mechanicalshock in a direction transverse to the longitudinal axis, or parallel tothe wafer discs. Each separator 27 is provided with a peripheral bump orembossment 27 c. The height (referring to the orientation of FIG. 4) ofthe peripheral embossment 27 c is greater than the sum of the height ofthe to side bumps 27 a and the wafer 25 thickness, but less than the sumof the heights of the bumps 27 a, 27 b in the wafer thickness. In thismanner, the embossment is high enough so as to cushion the edge of thewafer, yet short enough so as not to interfere with the cushioning ofthe bumps 27 a, 27 b against the wafers 25. The peripheral embossment 27c extends around the periphery of the separator. In the preferredembodiment, the peripheral embossment is continuous. However, theperipheral embossment can be discontinuous and contain gaps therein. Theseparator 27 has an outer or peripheral edge 27 d that interacts withthe vertical isolators, or cushions, 22 b. If the wafer stack issubjected to mechanical shock having a component parallel to the wafers,the wafer edge is cushioned by the “give” of the peripheral embossments27 c and by the cushions 22 b. The separators also prevent lateralmotion of the wafers, which motion can cause surface scratching of thewafers.

The wafer stack embodiment of FIGS. 6 and 7 is substantially similar tothat of FIG. 4. The wafer(s) 25 are separated by one or more plasticring separator(s). Plastic ring separator is an assembly having a rigidring 26 made of plastic and separator 27 made from the same said specialpolymer film having the same said embossments of 27 a, 27 b. The ring 26has a shoulder 26 a for receiving the wafer edge. The ring 26 thuscontains the wafer and prevents lateral movement. The separator 27 iscoupled to the ring 26 for which top side to provide a related step 26 aperipheral located designed in a manner to receive a packaged wafer 25.As the wafers are stacked, the separator bumps 27 a, 27 b may compress.If the wafers have protrusions, such as bond pads or solder balls, thedistance between wafers diminishes. This arrangement with the ring 26provides sufficient height to provide adequate clearance to protectsurfaces of elevated members such as ball bond pads located on thesurface of said wafer 25 packaged. In addition to the feature ofprotecting elevated members on surfaces of packaged wafer(s) 25 such asbond pads, separator 27 prevents damage due to corrosion, breakage andmishandling.

FIG. 8 is a top view of air-activated cushion 23 constructed from thesame said static dissipative sacrificial film used for the separators27, followed by shown cross-sectional view FIG. 9. Air activated cushion23 has multiple activating air valves 23 a, which automatically relatesto the volume of atmospheric air contained within said cushion 23. Eachvalve establishes a “rate” of discharge of air contained in the cushion23 dependant upon the amount of mechanical shock energy generated by any“impact” created by any mishandling of container 20 for which is themeans to absorb and or isolate shock of energy that could otherwisecause crack or outright breakage damage to one or more wafer(s) 25during transport phases to include shipment/storage stages. Whereas saidair valves 23 will act to reset said cushion 23 with the same saidatmospheric air when not under the stress of any “impacts”. This servesto maintain equal pressure on packaged wafers within container 20 thatserves to control both vertical motion along the longitudinal axis andlateral motion parallel to the wafers having the purpose to reducescratch and breakage damage while simultaneously serving the purpose inassisting removal of top cover thus minimizing even further waferdamaging possibilities.

The use of air cushions may cause air flow inside of the enclosure. Thisair flow contains AMCs from exterior sources and interior sources (suchas by outgassing). The use of the sacrificial film in both theseparators and cushions will intercept and capture AMCs.

Each cushion has a top wall 23 b, bottom wall 23 c and a side wall 23 dwhich is generally cylindrical, as well as a expandable fiber core 23 emade of a polymer having memory located inside of the walls. The wallsare made from a flexible film. The foam is compressible. A band 41 islocated around the side wail 23 d (see FIGS. 9 and 10). The band 41regulates flow of air between the film and the core 23 e andconsequently regulates the compression and expansion of the cushion 23.With the band 41, the response time to compress and expand the cushionis slower than without the band.

The wafer stack of FIG. 11 can have the wafers oriented eithervertically, such as in a POD, or horizontally, such as in a FOUP orFOSB. The wafer holder 51 may also be known as a wafer boat. The waferstack of FIG. 11 has no air cushions 23.

Regarding ESD, container 20 has surfaces greater than >10E11 ohms, whileseparators 27 and cushions 23 and bag 30 have dissipative surfacesranging from >10E5 to <10E11 ohms. This arrangement provides aconductive electrical circuit to grounding studs 32 (see FIG. 3) havinga surface resistance (SR) less than <10E5 ohms centrally located withintop cover 21 and bottom cover 22. This is the method to provide anelectrical path to earth ground for the purpose to protect packagedwafer(s) 25 from ESD events. A path for ESD is provided from the waferstack to ground 32A by way of the separators 27, the film 69 aroundcushions 23, and the grounding studs 32. Whereas this feature when addedto the feature of container 20 made of resins with no moisture absorbingactivated carbon or chemical additive constituents resulting ininsulative surfaces having a SR greater than >10E11 ohms for whicharrangement remains within the concepts of this invention, with thepurpose to isolate accumulation of environmental moisture vaporspossibly laced with environmental corrosive AMCs creating “corrosivesoups” to cause corrosive damage to packaged wafer(s) 25 within theenvironment of said container 20.

The container 20 or box is designed to be stacked so that severalcontainers 20 can be stacked together. When stacked, the top groundingstud 32 of the lower container contacts the bottom grounding stud of theupper adjacent container so as to provide electrical continuity toground.

The cushions 23, and in particular the walls 23 b, 23 c and 23 d of thecushions can be made out of the same polymer film 69 as the separators,which film will, isolate and intercept the AMCs. It is preferable toprovide one or more components of the wafer stack, namely the separatorsand/or cushions, made from the film so as to intercept and isolate theAMCs.

The film is considered to be sacrificial in that once it has been usedto intercept and capture AMCs, then over a period of time it will loseits ability to continue to intercept and capture AMCs. Therefore, thecomponents made from the film, should be considered to be for one timeuse only and should be disposed after use. Thus, when a fresh batch ofwafers is loaded into an enclosure, such as a container 20, then freshseparators 27 and cushions 23 should be included as well.

In addition to the separators 27 and cushions 23, the bag 30 can also bemade of the sacrificial polymer film 69, which film intercepts andisolates AMCs. The opening 31 of the bag is left open and unsealed. Thisallows air containing moisture vapors, and thus the AMCs, to enter andegress from the bag, wherein the film can perform its function tointercept and isolate the AMCs. The container 20 need not be scaled, andcan in fact be unsealed for the same purpose, namely to allow air flowto enter and exit the container, which air flow contains the moisturevapor and thus the AMCs. By locating the sacrificial film in a positionadjacent to the wafers, then the film will intercept and isolate theAMCs and thus prevent the AMCs from contaminating and causing corrosiondamage to the wafers.

Thus, the enclosure with the sacrificial film can be a rigid containersuch as a container 20 shown in the drawings, or a POD, FOUP or FOSB, ora flexible container, such as a bag 30, or a combination. An example ofa combination is a rigid container inside of the bag 30.

In addition to the separators being made of the film having sacrificialsurfaces, the film can be used elsewhere. FIGS. 12 and 13 show a POD 61.The POD has a bottom member 63, a top cover 65 and a wafer boat 67. Thewafer boat 67 contains the wafer stack 26. These components of the PODare conventional and commercially available.

The POD 61 is modified to provide the film having sacrificial surfacesoutside of the wafer stack 26 and inside of the POD 61. A film 69 of thesame sacrificial material as the separators 27 is provided outside ofthe wafer stack. The film can be of any shape or configuration. As shownin FIGS. 12 and 13, the film 69 forms the sides of a tube, where the topand bottom of the tube are open to receive the wafer boat. A support 71is provided to hold the film up in its tube, or vertical, configuration.The film 69 is located around the support 71. The film can be tacked orcoupled to the support, although this is not required. To access thewafer stack in the POD, the film is removed from the POD.

FIG. 15 shows a FOUP 75. The FOUP has side walls 77, a rear wall 79, atop wall 81, a bottom wall 83 and a door 85. A rack 87 is provided onthe side walls 77, which rack receives the wafers. The wafers areinserted into the rack to form a wafer stack. Film 69 is provided on theinside of the side walls 77, as well as the inside of the rear wall 79of the inside of the door 85. The film does not interfere with the useof the rack 87.

Thus, FIGS. 12-13, 15 show the use of film 69 that is external to thewafer stack, but internal of the enclosure.

The sacrificial film 69 can be provided in sheet form, or in otherforms, such as a pouch 91, as shown in FIGS. 16 and 17. The pouch 91 ismade of the film 69, folded along one side 93 and sealed along the othersides 95. The film is perforated with holes 97. Inside of the pouch arepieces or segments 99 of the film. These pieces are film that have beenchopped or cut so as to decrease their size. The pieces 99 are largerthan the holes 97 so that they remain inside of the pouch.

The sacrificial film 69, whether it is a sheet or a pouch, is coupled tothe walls of the container 75 by an adhesive. Any AMCs produced by theadhesive are intercepted and captured by the film. The film allows theuse of commercial containers such as PODs, FOUPs and FOSBs. Thecontainers are retrofitted with the film.

The enclosures shown in FIGS. 12 and 15 have ESD arrangements thatprovide paths to ground from the interior of the enclosure to theexterior. For a POD 61, as shown in FIGS. 13-14, the wafer stack 26contacts the film 69, which provides a path to ground 32A. A pouch 91Ais provided. The pouch 91A is substantially similar to the pouch 91. Apocket 101 is provided. The pocket 101 is formed by a sheet 103 of filmattached to the pouch 91. The pocket 101 is open at the bottom toreceive a support 105. A tab 109 of the film 69 extends from the pouchto a grounding stud 32, which can be a screw to allow replacement of thefilm and pouch. The pouch 91A is located at one of the open ends of thewafer boat. When installed in a POD, the edges of the wafers in thewafer stack 26 contacts the film 69 on the pouch 91A. The support isconductive, thus an electrical path to ground 32A is provided by way ofthe pouch 91A and the support 105.

As the wafer boat is placed into or removed from the base 63, the pouchcan be pushed away slightly so as not to catch the edges of the wafersduring insertion and removal. The support 105 is resilient and moves thepouch 91A into contact with the wafer stack 26. The pouch and supportare released. The pouches 91, 91A are resilient as well, and providesome cushioning to the edges of the wafers.

FIGS. 15 and 18 show a similar ESD arrangement for the FOUP 75 (and canbe used on a FOSB as well). The pouch 91A is secured to the rear wall 79by adhesives. A tab 109 of film 69 extends to a grounding stud 32. As awafer is inserted into the wafer stack 26, its edge contacts the pouch91A, thus having a path to ground, by way of the film in the pouch 91A,the grounding member 111 and the grounding stud 32, for an ESD event.

The use of a grounding path from the wafer stack 26 to ground 32A in anenclosure such as a POD, FOUP or FOSB allows the enclosure to befabricated with either activated carbon or chemical additives. Activatedcarbon and/or chemical additives are used to enhance ESD protection ofthe wafers, but increase damage to the AMCs.

The film has a limited useable life. After being used for so many cyclesof wafer stacks, the ability of the film to capture and seize becomesdegraded. The used film is replaced with fresh film and the containerremains in use in processing and transporting wafers.

The foregoing disclosure and showings made in the drawings are merelyillustrative of the principles of this invention and are not to beinterpreted in a limiting sense.

1. A packaging system for intercepting and capturing mechanical shockenergy and corrosive contaminants for the protection of IC wafers duringfabrication, transport, and storage phases, such wafers having surfacecomponents such as bond pads, solder balls and interconnects which aresusceptible to damage due to corrosion, mechanical shock or electricalstatic discharge, comprising: a) an enclosure having an interior volume;b) a wafer stack located in the interior volume, the wafer stackcomprising plural wafers and separators in contact with the wafers, theseparators are sheets each having two sides and having raised bumpsextending from each side of the separator sheet, the bumps creatingspaces between the respective separator and the respective wafer, whichspaces allow air to flow there through; c) at least one of theseparators made of a polymer film material having the properties tointercept and capture airborne molecular contaminants (AMCs) belongingto either or both chemical organic and inorganic families for which saidmaterial is dissipative to static discharge.
 2. The package of claim 1wherein the separator is static dissipative made of a plastic filmmaterial having at least two layers with one comprising of activatedcarbon and the second layer having a component taken from the metallicgroup of copper, aluminum, tin, silver and a rare earth.
 3. Thepackaging system of claim 1, wherein: a) the wafers have edges subjectto mechanical shock; b) the separators are sheets, the separators haveperipheral rings located adjacent to the wafer edges so as to protecteach associated packaged wafer edge from shock or physical damage. 4.The packaging system of claim 3 wherein the peripheral rings areembossed in the separator sheets.
 5. The packaging system of claim 3further comprising a rigid support ring made of a polymer locatedadjacent to the separator, the wafers being supported by the supportring.
 6. The packaging system of claim 2, further comprising: a) atleast one cushion located in the wafer stack, the cushion comprises acompressible core and a flexible envelope around the core, the envelopehaving vents to allow gas to pass in and out of the top and bottomcushions at a controlled rate, the top and bottom cushions havingsidewalls that compress when the top and bottom cushions are compressed;b) a flexible band around the side wall of at least one of the top andbottom cushions, the band located outside of the cushion envelope andcontrolling the flow of gas into and out of the respective cushion. 7.The packaging system of claim 1 wherein the enclosure is a plastic rigidho having insulative surfaces.
 8. The packaging system of claim 7wherein the wafer stack is dissipative to static discharge.
 9. Thepackaging system of claim 7, wherein: a) the arrangement of packagedwafers, separators and cushions all having dissipative surfaces willprovide electrical path to earth ground; b) the box can be stacked ontosimilar boxes; c) the box having top and bottom conductors on theoutside and providing an electrical path to earth ground for the waferstack; d) the top or bottom conductors being m contact with the to orbottom conductors of an adjacent box stacked with the one box.
 10. Thepackaging system of claim 1 wherein the enclosure is a bag.
 11. Thepackaging system of claim 1 wherein the enclosure is a rigid box withina bag.
 12. (canceled)
 13. (canceled)
 14. (canceled)
 15. (canceled) 16.(canceled)
 17. (canceled)